Multifunction devices having functions of a photocopier, scanner, printer, facsimile machine and the like have been known. In the meanwhile, along with the development of communication networks, there has been such a technology that the multifunction device is connected to a control device constituted by a personal computer (PC) via a communication network, the control device supplies document data to the multifunction device, and the multifunction device forms a document image corresponding to the document data or the multifunction device causes the software of the PC to run.
For example, Japanese Laid-Open Patent Application No. 10-111793 (published on Apr. 28, 1998) discloses a technique which is arranged as follows. A host PC supplies menu item information including a service ID and menu display data to a multifunction device, for each of the services provided by the host PC. On the other hand, the multifunction device manages the supplied menu item information as a menu table, and displays the menu items on the operation panel. Then, in response to the input by the user, the multifunction device determines which menu item has been selected, and supplies the selection result to a control device. The control device executes an application corresponding to the notified selection result. In response to the execution of the application, functions such as a scanning function and a printer function of the multifunction device are activated from the control device side.
As described above, Japanese Laid-Open Patent Application No. 10-111793 (published on Apr. 28, 1998) teaches that a function of the multifunction device is activated from the host PC side, in response to the execution of an application. However, different multifunction devices have different sets of functions.
FIG. 32 shows a conventional multifunction device. As shown in this figure, the multifunction device 101 includes an OS layer 15, a driver layer 14, a service layer 13, an application layer 12, and a user interface layer 11. These layers are unique to the multifunction device 101, and hence different types of multifunction devices have different sets of layers.
Even if the same function is shared between plural multifunction devices, these devices may process the shared function in different ways. For this reason, in case where control of the multifunction device in accordance with an application is performed by a control device, the control device is required to chose a control command suitable for the type of the multifunction device. As a result, the efficiency in the development of a new application by which the control device controls the multifunction device is deteriorated.
Japanese Laid-Open Patent Application No. 10-111793 (published on Apr. 28, 1998) teaches that a multifunction device manages a menu table regarding display menus. In this case, when a control device controls the multifunction device in accordance with a new application, it is necessary to add a corresponding new menu item. If it is necessary to input a parameter for the control, a screen for the input must be displayed on an operation panel of the multifunction device. The multifunction device must therefore manage data for the input screen. As a result, in case where a control device controls the multifunction device in accordance with a new application, corresponding menu items, data of the input screen, and a program for displaying the data must be provided in the multifunction device, which is very troublesome.